Method of cleaning castings



Oct. 6, 1953 A. WALCHER METHOD OF CLEANING CASTINGS Filed Aug. 28, 1948 Patented Oct. 6, 1953 METHOD OF CLEANING CASTINGS Alfred Walcher, Chicago, Ill., assignor to American Steel Foundries, Chicago, 111., a corporation of New Jersey Application August 28, 1948, Serial No. 46,586

4 Claims.

This invention relates to the production of castings and more particularly to a novel process for cleaning sand cores, chills, and mold sand from castings after they have been stripped from their molds.

According to prior art practice, such castings have been cleaned by vibrating or by rapping the castings; however, cleaning of certain types of castings, such as large hollow steel members, has been a tedious and expensive process for steel foundries inasmuch as it has been necessary to suspend such castings and rap them for hours in order to remove the sand cores and chills there from.

According to the present invention, it has been discovered that such castings can be completely and efliciently cleaned within a few minutes by immersing the castings in water after they have been stripped from the molds and while they are still at a temperature sumciently great to develop steam pressure capable of blasting the cores and chills therefrom.

This novel process not only reduces the cleaning time but also eliminates the necessity of mechanically rapping or vibrating the castings and the consequent possibility of damage thereto.

The foregoing and other objects and advantages of the invention will become apparent from a consideration of the following specification and the accompanying drawings which are lithographic reproductions of actual photographs illustrating the process.

In the drawings:

Figure 1 shows a motor housing casting after it has been stripped from the mold;

Fig. 2 shows the casting suspended by a hoist immediately prior to immersion of the casting in water;

Figure 3 shows the casting immediately after it has been removed from the water.

Describing the novel process in detail and referring first to Figure 1, the casting shown therein is a hollow motor housing casting weighing approximately 2500 pounds, finished, and is shown after having been stripped from the mold. The casting is generally designated 2 and comprises a plurality of risers 4 and a gate 6. The casting contains a central core 8 reinforced by rods l0.

Referring to Figure 2, the casting is illustrated as suspended over a body of water by a chain 12 connected to a conventional hoist M.

An explosion results when the casting is immersed in the water and it may be noted that a series of such explosions usually occur, blasting all cores, chills, and mold sand from the casting. Preferably the water is agitated by raising and lowering the casting beneath the surface of the water.

After the casting has been removed from the water, it appears as in Figure 3 entirely cleaned preparatory to removal of the gate and risers.

The novel process is practiced with respect to motor housing castings of the type illustrated by first stripping from the molds all castings poured from a single heat. The time interval between stripping and immersion in the water is quite flexible inasmuch as the process may be practiced within a wide range of temperatures. Normally, the time interval between pouring of the castings and stripping from the molds is approximately four hours. After the castings have been stripped from the mold, they are preferably loaded in freight cars and are permitted to cool for a time interval of about six to nine hours dependent upon temperature and weather conditions. Subsequent to this cooling period, the castings are immersed in the water, as above described in connection with the drawings.

It has been determined that castings of this type can be cleaned by the above-described process, by immersing the castings at a temperature value of approximately 600 F. and higher, preferably within a range of within 600 to 1100. However, it will be understood that the process may be applied to castings of various sizes and temperatures provided that the castings are immersed at a temperature value sufiicient to develop adequate steam pressure therein to blast the cores and mold sand therefrom. Furthermore, while the process has been described in connection with the cleaning of castings which are produced in individual molds, it will be understood that the process may also be applied to a plurality of castings produced in a single mold and connected by a runner or runners to form a unit which may be immersed, as above described.

I claim:

1. A method of cleaning core sand from the interior of a hollow ferrous metal casting which has been removed at a temperature value of at least about 600 F. from a mold, said method comprising submersing the casting in a body of water at atmospheric pressure while said casting is at an internal residual temperature of at least about 600 F.

2. A method of cleaning core sand from the interior of a hollow steel casting which has been removed from a mold at a temperature value exceeding 600 F., said method comprising air cooling the casting, and then submersing the casting in a body of water at atmospheric pressure before the casting has cooled from its mold temperature to a temperature value below 600 F. and below the temperature value at which said water volatilizes whereby the residual heat in said casting without otherwise heating the same is sufi'lcient to rapidly volatilize said water thereby blasting the core sand from the interior of the casting.

3. A method, according to claim 2, wherein the steel casting is raised and lowered within the water to agitate the same until the sand has been blasted from the interior of the casting.

4. A method of cleaning core sand from the interior of a hollow ferrous r'ijtal casting, said method comprising blasting the sand from the interior of said casting by lowering the casting into the body of water at atmospheric treasure while said casting is at a residual internal tem- ALFRED WALCHER.

iieferehees Cited in the me of this patent UNITED STATES PATENTS Number 1 15 70 fb fl 13984399 2,016,376 2019 2 06 2,527,666

Name Date Peterson Nov. 9, 1915 near May 2'7, 1919 n'rg Feb. 21, 1933 Koch Oct. 8, 1935 Williams Oct. 29, 1935 Winter Oct. 31, 1950 

1. A METHOD OF CLEANING CORE SAND FROM THE INTERIOR OF A HOLLOW FERROUS METAL CASTING WHICH HAS BEEN REMOVED AT A TEMPERATURE VALUE OF AT LEAST ABOUT 600* F. FROM A MOLD, SAID METHOD COMPRISING SUBMERSING THE CASTING IN A BODY OF WATER AT ATMOSPHERIC PRESSURE WHILE SAID CASTING IS AT AN INTERNAL REDISUAL TEMPERATURE OF AT LEAST ABOUT 600* F. 